Patient handout

Immune-related adverse events (irAE) — checkpoint inhibitor toxicity management

PRODUCTION

1. Your condition

This handout is for immune-related adverse events (irae) — checkpoint inhibitor toxicity management. Your care team identified this based on: active checkpoint inhibitor therapy (pd-1/pd-l1/ctla-4/lag-3) with new symptom or laboratory abnormality of any organ system — irae until proven otherwise (nccn 2024).

Other reasons your team may use this plan: any troponin elevation in an ici patient — stat cardiology + stat empiric methylprednisolone 1 g iv (mahmood jacc 2018 pmid 29567210); diarrhea >4 stools above baseline, or any bloody stool, in an ici patient — suspect colitis (nccn 2024); new dyspnea, cough, hypoxia in an ici patient — suspect pneumonitis; hrct chest (nccn 2024).

2. Your medications

Take these medications exactly as prescribed. Do not stop or change a dose without talking to your provider.

Medication	Starting dose	How	When	What it does
prednisone	1 mg/kg/day (max 80 mg) PO	PO	once daily then taper over 4-6 weeks	NCCN 2024 / ASCO 2021 (Schneider PMID 34724392) — grade 2 colitis: hold ICI, start oral prednisone 1 mg/kg, taper over 4-6 wk
budesonide	9 mg PO once daily	PO	once daily	Oral budesonide (ileal release) for mild-moderate colitis or as steroid-sparing during taper
methylprednisolone	1-2 mg/kg/day IV	IV	q24h	NCCN 2024 — grade 3-4 colitis: IV methylprednisolone 1-2 mg/kg/d; transition to oral once improving
infliximab	5 mg/kg IV	IV	one dose; may repeat at 2 weeks if needed	NCCN 2024 / ESMO 2022 (Haanen PMID 36270461) — infliximab for steroid-refractory ICI colitis; rapid response typical
vedolizumab	300 mg IV	IV	weeks 0, 2, 6 then q8w	NCCN 2024 — gut-selective vedolizumab for steroid-dependent or infliximab-refractory ICI colitis (Bergqvist 2017)

Plan: ICI colitis — steroids -> infliximab -> vedolizumab

4. When to seek emergency care

Call 911 or go to the nearest emergency room right away if you have:

ANY troponin elevation in an ICI patient — empirically treat as myocarditis; do not wait for cardiac MRI or biopsy (Mahmood JACC 2018 PMID 29567210)(life-threatening)
Grade 3-4 ICI pneumonitis with oxygen level (SpO₂) <90% on RA or O2 requirement >4 L/min(life-threatening)
Grade 4 ICI colitis with bowel perforation or toxic megacolon(life-threatening)
ALT >20x ULN or bilirubin >3x ULN with INR rise — fulminant ICI hepatitis(life-threatening)
Hypotension + hyponatremia + hyperkalemia in ICI patient — secondary adrenal insufficiency from hypophysitis; primary adrenal irAE rare(life-threatening)
Guillain-Barre or myasthenia-like syndrome with rising NIF, vital capacity drop, bulbar symptoms — impending respiratory failure(life-threatening)
Combined myocarditis + myositis + myasthenia-like syndrome (Triple-M) — worse prognosis than any alone(life-threatening)

5. Follow-up

Steroid taper over 4-6 wk minimum; PJP prophylaxis (TMP-SMX 3x/wk) if prednisone >20 mg for >4 wk; PPI; calcium + vitamin D + bisphosphonate for long-term steroid; endocrinopathy permanent replacement (levothyroxine, hydrocortisone, insulin); rechallenge decision per NCCN 2024 — most G3 + all G4 myocarditis/pneumonitis/encephalitis/hepatitis permanently discontinue; G2 rechallenge feasible after resolution. Multidisciplinary cancer follow-up with primary oncology team for alternative therapy if permanent d/c (NCCN 2024)

6. Sources

Guideline: NCCN Immune-Related Toxicities 2024 + ASCO 2021 irAE (Schneider JCO 2021) + ESMO 2022 immunotherapy toxicity (Haanen Ann Oncol 2022)